Apple applications getting slower and slower on WiFi until connection is completely halted

Hello,

I have a MacBook Air (Early 2014) on macOS 10.14(.5, although it occurred on 10.14 as well) that has recently picked up a nasty issue.

When booting up, the WiFi works just fine on Safari, the App Store, Maps, etc. As I continue to use it, the laptop gets slower and slower with connection until it is entirely halted and the loading bar doesn't pass even a sixth of the way.

I do not have this issue if I boot it up using a Thunderbolt 2 to Ethernet adapter and do not use the WiFi at all. However, if I do enable the WiFi and temporarily do not use Ethernet, the issue will present itself eventually. Plugging the Ethernet cable back in and disabling WiFi still won't allow me to access websites, that's the only way to get the issue to carry over to Ethernet.

Oddly enough, even after all of these issues, Firefox and Google Chrome still connect just as well as when first booted. Full speed, works great. It's just Apple applications like the before named Safari, App Store, and Maps.